Seebeck Enhancement Through Miniband Conduction in III–V Semiconductor Superlattices at Low Temperatures

We present theoretically that the cross-plane Seebeck coefficient of InGaAs/InGaAlAs III?CV semiconductor superlattices can be significantly enhanced through miniband transport at low temperatures. The miniband dispersion curves are calculated by self-consistently solving the Schr?dinger equation with the periodic potential, and the Poisson equation taking into account the charge transfer between the two layers. Boltzmann transport in the relaxation-time approximation is used to calculate the thermoelectric transport properties in the cross-plane direction based on the modified density of states and group velocity. It is found that the cross-plane Seebeck coefficient can be enhanced more than 60% over the bulk values at an equivalent doping level at 80?K when the Fermi level is aligned at an edge of the minibands. Other thermoelectric transport properties are also calculated and discussed to further enhance the thermoelectric power factor.     

Study of removal of Direct Yellow 12 by cadmium oxide nanowires loaded on activated carbon

In this research, cadmium oxide nanowires loaded on activated carbon (CdO-NW-AC) has been synthesized by a simple procedure and characterized by different techniques such as XRD, SEM and UV–vis spectrometry. This new adsorbent has been efficiently utilized for the removal of the Direct Yellow 12 (DY-12) from wastewater. To obtain maximum DY-12 removal efficiency, the influences of variables such as pH, DY-12 concentration, amount of CdO-NW-AC, contact time, and temperature have been examined and optimized in a batch method. Following the variable optimization, the experimental equilibrium data (at different concentration of DY-12) was fitted to conventional isotherm models such as Langmuir, Freundlich and Tempkin. The applicability of each method is based on the R² and error analysis for each model. It was found that the experimental equilibrium data well fitted to the Langmuir isotherm model. The dependency of removal process to time and the experimental data follow second order kinetic model with involvement of intraparticle diffusion model. The negative value of Gibbs's free energy and positive value of adsorption enthalpy show the spontaneous and endothermic nature of adsorption process.     

Application of electrostatic pull-in instability on sensing adsorbate stiffness in nanomechanical resonators

Recent theoretical and experimental research showed that the response of micro/nanocantilevers to detect materials is not always simply related to extra mass. Stiffness of adsorbates and surface stress-induced changes in the stiffness, arising from adsorption, can produce frequency shifts that are several times greater in magnitude than those induced by mass loading. Consequently, the calculated adsorbed mass does not fully represent the real adsorbed mass, making the measurements qualitative. Therefore, a proper method for measuring the stiffness of adsorbed layers has to be combined with resonance frequency measurement to quantitatively analyze changes in both the mass and the stiffness. This letter presents the theory for application of electrostatic pull-in instability for measuring the stiffness of adsorbates at the surface of cantilever resonators.     

Central Amygdalar and Dorsal Striatal NMDA Receptor Involvement in Instrumental Learning and Spontaneous Behavior.

Glutamate-coded signaling in corticostriatal circuits has been shown to be important in various forms of learning and memory. In the present study, the authors found that N-methyl-D-aspartate (NMDA) receptor antagonism in the central nucleus of the amygdala (CeA) and the posterior lateral striatum (PLS) impaired instrumental conditioning but had no effect in the anterior dorsal striatum. NMDA receptor antagonism in the CeA and PLS also affected spontaneous motor behavior and certain aspects of feeding. The present findings extend knowledge of the dynamic neurophysiological processes, instantiated in a complex neural network, required for instrumental learning in the mammalian brain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Current signature analysis of induction motor mechanical faults by wavelet packet decomposition

This paper presents a novel approach to induction motor current signature analysis based on wavelet packet decomposition (WPD) of the stator current. The novelty of the proposed method lies in the fact that by using WPD method the inherent nonstationary nature of stator current can be accurately considered. The key characteristics of the proposed method are its ability to provide feature representations of multiple frequency resolutions for faulty modes, ability to clearly differentiate between healthy and faulty conditions, and its applicability to nonstationary signals. Successful implementation of the system for two types of faults, i.e., rotor bar breakage and air-gap eccentricity is demonstrated here. The results are validated based on both simulation and experiments of a 5-hp induction motor.     

Application of laccases with cellulases on denim for clean effluent and repeatable biowashing

In this study, we try to use laccases with cellulases to investigate their effects on the garments and possible reusing of biowashing effluent to save water, enzyme, and energy. To achieve these goals, denim garments treated with different percentages of laccases and cellulases and the remaining baths (effluent) used three times with three different methods. Color indices of fabric samples were measured by colorimeter on the front and back of garment and on the white pocket. The effluents in the remaining baths were also monitored by spectrophotometer after each processing. The XRD spectrums were used to calculate the crystalline degrees of the chosen samples. The fiber surfaces of some treated samples were observed by SEM. The results revealed that using optimum concentration of laccases and cellulases produces the same biowashing effect on the garment after three‐repeated biowashing. By using this method, laccases helps to discolor the effluent and enzyme residuals of both cellulases and laccases are useful for repeated processing. Overall, this method is recommending a biowashing process with considerable reduce in consumption of laccases, cellulases, water, time, and energy. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

The Role of Architectural Considerations in Seismic Performance of Buildings： A Case Study in Iran

Experience from recent earthquakes such as Gilan, Zanjan, Bam and Lorestan earthquakes in Iran indicated that the constructed buildings are vulnerable against earthquake. Vulnerability of these structures is due to various reasons such as designing without considering seismic regulations, problems of regulations （design goals）, implementation problems, changing of the building occupancy class, increasing the weight of building stories, adding new stories to the building and changing in architecture of building without considering structural system. So the main objective of this research is to examine the features of building configuration and their effects as for the damages to buildings in past earthquakes. For this purpose, initially four occurred earthquakes in Iran are selected as case study. Then three types of buildings （steel structure, concrete structure and masonry buildings） are analyzed with details. Results showed that the most of damages are occurred in the old steel structures and masonry buildings which their ages are more than 25 years. The study showed that most of the buildings in the study area are steel structure and masonry buildings while concrete structures are infrequent which most of them had no or slight damages. Therefore, the importance and need to enhance the performance of available buildings against earthquake forces by rehabilitating methods would be more important than before. Also results indicated that the decisions related to architectural plan which have significant effect on seismic performance of buildings, can be divided into three categories： configuration of building, restrictive formal architectural plan and dangerous structural components, as these categories are not obstacle of each other, it is possible that each category has an influential effect on others. So organizing the design decisions in this way is very important so as to manage their effects and interdependencies.